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 * Copyright (C) Codehaus.org                                                *
 * ------------------------------------------------------------------------- *
 * Licensed under the Apache License, Version 2.0 (the "License");           *
 * you may not use this file except in compliance with the License.          *
 * You may obtain a copy of the License at                                   *
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 * http://www.apache.org/licenses/LICENSE-2.0                                *
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package com.googlecode.lazyparsec;

import java.util.ArrayList;
import java.util.List;

/**
 * A parser that always returns an empty mutable list.
 *
 * @author Ben Yu
 */
final class EmptyListParser<T> extends Parser<List<T>> {
    @SuppressWarnings("unchecked")
    private static final EmptyListParser singleton = new EmptyListParser();

    @SuppressWarnings("unchecked")
    static <T> Parser<List<T>> instance() {
        return singleton;
    }

    private EmptyListParser() {
    }

    @Override
    boolean apply(ParseContext context) {
        context.result = new ArrayList<T>(0);
        return true;
    }

    @Override
    public String toString() {
        return "[]";
    }
}
